Heat Pumps FAQ

Cart Contents


1. How do I size up a heat pump?
A. Sizing guide

Type of Pool Pool Size
Litres Summer Only Extended +
Above 3.5 - 6.6 Up to 38000 E.Heat 55 E.Heat 80
Above 7 Up to 57000 E.Heat55/E.Heat 80 E.Heat 85
Above 8 Up to 76000 E.Heat 80 E.Heat 105
Above 9 Up to 95000 E.Heat 85 E.Heat 125
Inground 3.5 x 7 Up to 38000 E.Heat 80 E.Heat 85
Inground 4 x 8.5 Up to 57000 E.Heat 80 E.Heat 105
Inground 5 x 10 Up to 76000 E.Heat 85 E.Heat 125
Inground 5.5 x 11 Up to 95000 E.Heat 105 E.Heat 150
Inground 6 x 12 Up to 114000 E.Heat 150 Contact Waterco
Inground 6 x 15 Up to 133000 E.Heat 150 Contact Waterco

B. Rule of Thumb Calculation

Another easy way to size the required heat pump is by multiplying the evaporating surface area of the pool in square meters by .58 kW which will give you the required kW for extended use.

Example: 5 x 10 = 50 square meters x .58 = 29kW, so the next size up which is the 31 kW model would be recommended. Remember there is no such thing as a heat Pump pool heater being too big!

Please note:  Swimming pools with negative edges and water features require special attention due to excessive heat losses.

2. How long will it take to heat up the pool?
The ElectroHeat is designed to economically heat a pool maintaining the desired water temperature at all times. The ElectroHeat will effectively heat your pool when the ambient air temperature reaches 10 deg. C or more. ElectroHeat's performance will fluctuate depending on water and weather conditions.

In general, compared to other types of pool heaters such as gas, the heat pump has a lower heating capacity on a kW/hr basis. Therefore it will be required to operate longer to accomplish the desired results. At certain times, it maybe necessary to run the heat pump up to 24 hours a day.

The ElectroHeat at the start, will heat slowly but at 21deg C and more, it will perform well maintaining the desired water temperature at a very low cost and could run as little as 2 hours per day in the process.

Between 10deg C to 18deg C, it will increase your water temperature by 3deg C to 5.5deg C a day. Over 21deg C you should obtain an increase up to 0.8deg C an hour and over 26deg C up to 1.1deg C an hour depending on the size of the pool, the size of the heat pump, the water temperature, and the ambient temperature at the moment of operation.

ElectroHeat is capable of heating water up to a temperature of 40deg C and more if required, depending on water and ambient air temperature at the time of operation.

As with all pool heaters, you are advised to use a pool cover at night and when the pool is not in use. This will keep evaporation, the greatest source of heat loos, to a minimum, greatly reducing the overall pool heating costs.

3. How much will it cost to run?
kW/hr x cost per kW = cost of operation per hour

Here is an estimate for Sydney (note: subject to changes in electricity costs)

  • 45,000 litre pool - uncovered
  • Electroheat 80
  • To maintain 28deg C
  • Electricity cost $0.125 kW/hr
  • Yearly heating cost - $1237.60

4. What is running cost difference between Heat Pump and Gas Heater
Gas heaters are the fastest method for heating your pool, providing a comfortable temperature for swimming on demand. Gas is best for heating pool & spas for short periods of time. Gas heaters can easily maintain any desired temperature regardless of the weather. Gas heaters are effective, but expensive to operate.

Heat pumps do not heat up the swimming pool as fast as gas heaters, but they are the most cost effective method of heating your pool all year round. Heat pumps use a small amount of electricity. The heat comes from the ambient air. Heat pumps can only operate efficiently in climates with ambient temperatures above 7deg. C


View Cart